Data Transmission Service:Migrate data from an OceanBase database in MySQL mode to an RDS for MySQL instance

Hard limits

Data type handling

Verify that the default precision settings for FLOAT and DOUBLE meet your requirements before starting the migration.

Allowed operations on the source database during migration

Considerations

• Database naming: If the source database name does not follow ApsaraDB RDS for MySQL naming conventions, create the destination database manually before configuring the task. Then use object name mapping to rename it during the Configure Objects and Advanced Settings step.

• Failed task retry: DTS retries failed migration tasks for up to seven days. Before switching workloads to the destination, stop or release any failed tasks — or run REVOKE to remove DTS write permissions on the destination — to prevent source data from overwriting destination data when the task resumes.

• DDL failures in destination: If DDL statements fail to execute in the destination, the DTS task continues running. Check task logs for details. See View task logs.

• Post-migration verification: After migration completes, run ANALYZE TABLE <table_name> to confirm data was written successfully. In high-availability (HA) switchover scenarios, data may exist only in memory and can be lost if not persisted.

• Source database performance: Full data migration increases load on both source and destination. Run migrations during off-peak hours and enable throttling if needed.

• Destination tablespace size: Concurrent INSERT operations during full migration cause table fragmentation. The destination tablespace will be larger than the source after migration completes.

Step 1: Go to the Data Migration Tasks page

1. Log on to the Data Management (DMS) console.

2. In the top navigation bar, click DTS.

3. In the left-side navigation pane, choose DTS (DTS) > Data Migration.

   You can also go directly to the Data Migration Tasks page. Console layout may vary — see Simple mode and Customize the layout and style of the DMS console for navigation options.

4. From the drop-down list next to Data Migration Tasks, select the region where the migration instance will reside.

   In the new DTS console, select the region in the upper-left corner instead.

Step 2: Configure source and destination databases

Click Create Task. On the Create Data Migration Task page, configure the following parameters.

Source database

Destination database

Step 3: Test connectivity and configure the IP address whitelist

Click Test connectivity and proceed.

If your source or destination database uses an IP address whitelist, add the CIDR blocks of DTS servers to that whitelist.

Step 4: Select migration types and objects

Configure the following parameters.

Migration types

Select the migration type based on your downtime requirements.

Object and advanced settings

Parameter	Description
Method to migrate triggers in source database	Available when schema migration is selected. Choose based on your requirements. See Synchronize or migrate triggers.
Processing mode of conflicting tables	Precheck and report errors: fails precheck if source and destination share table names. Ignore errors and proceed: skips the check, but risks data inconsistency or partial migration failure.
Capitalization of object names in destination instance	Controls the case of database names, table names, and column names in the destination. Default: DTS default policy. See Specify object name capitalization.
Source objects	Select objects from the Source objects section and move them to Selected objects using the icon. Selectable at the column, table, or database level.
Selected objects	Right-click an object to rename it. Click Batch edit to rename multiple objects at once. See Map object names. To set row filter conditions, right-click a table and specify WHERE conditions. See Set filter conditions.

Object name mapping may cause dependent objects to fail migration. Column mapping for non-full table migration, or schema mismatches between source and destination, can result in data loss for unmapped columns.

Step 5: Configure advanced task settings

Click Next: Advanced settings and configure the following.

Step 6: Run the precheck

Click Next: Save task settings and precheck.

To preview the OpenAPI parameters for configuring this task via API, hover over Next: Save task settings and precheck and click Preview OpenAPI parameters.

DTS runs a precheck before the migration task can start.

• If a check item fails: click View details, resolve the issue, and click Precheck again.

• If a check item shows an alert: determine whether it can be safely ignored. To ignore it, click View details > Ignore > OK > Precheck again. Ignoring alerts may cause data inconsistency.

Wait until the success rate reaches 100%.

Step 7: Purchase the migration instance and start the task

1. Click Next: Purchase instance.

2. On the Purchase instance page, configure the following:

   Section	Parameter	Description
   New instance class	Resource group settings	The resource group for the migration instance. Default: default resource group. See What is Resource Management?
   	Instance class	The instance class determines migration speed. See Specifications of data migration instances.

3. Read and select the Data Transmission Service (Pay-as-you-go) Service Terms check box.

4. Click Buy and start.

The migration task starts. Track progress in the task list.